[linux-block.git] / net / openvswitch / flow.c

/*
 * Copyright (c) 2007-2013 Nicira, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA
 */

#include "flow.h"
#include "datapath.h"
#include <linux/uaccess.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <net/llc_pdu.h>
#include <linux/kernel.h>
#include <linux/jhash.h>
#include <linux/jiffies.h>
#include <linux/llc.h>
#include <linux/module.h>
#include <linux/in.h>
#include <linux/rcupdate.h>
#include <linux/if_arp.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/sctp.h>
#include <linux/smp.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/icmp.h>
#include <linux/icmpv6.h>
#include <linux/rculist.h>
#include <net/ip.h>
#include <net/ip_tunnels.h>
#include <net/ipv6.h>
#include <net/ndisc.h>

u64 ovs_flow_used_time(unsigned long flow_jiffies)
{
	struct timespec cur_ts;
	u64 cur_ms, idle_ms;

	ktime_get_ts(&cur_ts);
	idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
	cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
		 cur_ts.tv_nsec / NSEC_PER_MSEC;

	return cur_ms - idle_ms;
}

#define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))

void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb)
{
	struct flow_stats *stats;
	__be16 tcp_flags = flow->key.tp.flags;
	int node = numa_node_id();

	stats = rcu_dereference(flow->stats[node]);

	/* Check if already have node-specific stats. */
	if (likely(stats)) {
		spin_lock(&stats->lock);
		/* Mark if we write on the pre-allocated stats. */
		if (node == 0 && unlikely(flow->stats_last_writer != node))
			flow->stats_last_writer = node;
	} else {
		stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
		spin_lock(&stats->lock);

		/* If the current NUMA-node is the only writer on the
		 * pre-allocated stats keep using them.
		 */
		if (unlikely(flow->stats_last_writer != node)) {
			/* A previous locker may have already allocated the
			 * stats, so we need to check again.  If node-specific
			 * stats were already allocated, we update the pre-
			 * allocated stats as we have already locked them.
			 */
			if (likely(flow->stats_last_writer != NUMA_NO_NODE)
			    && likely(!rcu_dereference(flow->stats[node]))) {
				/* Try to allocate node-specific stats. */
				struct flow_stats *new_stats;

				new_stats =
					kmem_cache_alloc_node(flow_stats_cache,
							      GFP_THISNODE |
							      __GFP_NOMEMALLOC,
							      node);
				if (likely(new_stats)) {
					new_stats->used = jiffies;
					new_stats->packet_count = 1;
					new_stats->byte_count = skb->len;
					new_stats->tcp_flags = tcp_flags;
					spin_lock_init(&new_stats->lock);

					rcu_assign_pointer(flow->stats[node],
							   new_stats);
					goto unlock;
				}
			}
			flow->stats_last_writer = node;
		}
	}

	stats->used = jiffies;
	stats->packet_count++;
	stats->byte_count += skb->len;
	stats->tcp_flags |= tcp_flags;
unlock:
	spin_unlock(&stats->lock);
}

/* Called with ovs_mutex. */
void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *ovs_stats,
			unsigned long *used, __be16 *tcp_flags)
{
	int node;

	*used = 0;
	*tcp_flags = 0;
	memset(ovs_stats, 0, sizeof(*ovs_stats));

	for_each_node(node) {
		struct flow_stats *stats = ovsl_dereference(flow->stats[node]);

		if (stats) {
			/* Local CPU may write on non-local stats, so we must
			 * block bottom-halves here.
			 */
			spin_lock_bh(&stats->lock);
			if (!*used || time_after(stats->used, *used))
				*used = stats->used;
			*tcp_flags |= stats->tcp_flags;
			ovs_stats->n_packets += stats->packet_count;
			ovs_stats->n_bytes += stats->byte_count;
			spin_unlock_bh(&stats->lock);
		}
	}
}

void ovs_flow_stats_clear(struct sw_flow *flow)
{
	int node;

	for_each_node(node) {
		struct flow_stats *stats = rcu_dereference(flow->stats[node]);

		if (stats) {
			spin_lock_bh(&stats->lock);
			stats->used = 0;
			stats->packet_count = 0;
			stats->byte_count = 0;
			stats->tcp_flags = 0;
			spin_unlock_bh(&stats->lock);
		}
	}
}

static int check_header(struct sk_buff *skb, int len)
{
	if (unlikely(skb->len < len))
		return -EINVAL;
	if (unlikely(!pskb_may_pull(skb, len)))
		return -ENOMEM;
	return 0;
}

static bool arphdr_ok(struct sk_buff *skb)
{
	return pskb_may_pull(skb, skb_network_offset(skb) +
				  sizeof(struct arp_eth_header));
}

static int check_iphdr(struct sk_buff *skb)
{
	unsigned int nh_ofs = skb_network_offset(skb);
	unsigned int ip_len;
	int err;

	err = check_header(skb, nh_ofs + sizeof(struct iphdr));
	if (unlikely(err))
		return err;

	ip_len = ip_hdrlen(skb);
	if (unlikely(ip_len < sizeof(struct iphdr) ||
		     skb->len < nh_ofs + ip_len))
		return -EINVAL;

	skb_set_transport_header(skb, nh_ofs + ip_len);
	return 0;
}

static bool tcphdr_ok(struct sk_buff *skb)
{
	int th_ofs = skb_transport_offset(skb);
	int tcp_len;

	if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
		return false;

	tcp_len = tcp_hdrlen(skb);
	if (unlikely(tcp_len < sizeof(struct tcphdr) ||
		     skb->len < th_ofs + tcp_len))
		return false;

	return true;
}

static bool udphdr_ok(struct sk_buff *skb)
{
	return pskb_may_pull(skb, skb_transport_offset(skb) +
				  sizeof(struct udphdr));
}

static bool sctphdr_ok(struct sk_buff *skb)
{
	return pskb_may_pull(skb, skb_transport_offset(skb) +
				  sizeof(struct sctphdr));
}

static bool icmphdr_ok(struct sk_buff *skb)
{
	return pskb_may_pull(skb, skb_transport_offset(skb) +
				  sizeof(struct icmphdr));
}

static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
{
	unsigned int nh_ofs = skb_network_offset(skb);
	unsigned int nh_len;
	int payload_ofs;
	struct ipv6hdr *nh;
	uint8_t nexthdr;
	__be16 frag_off;
	int err;

	err = check_header(skb, nh_ofs + sizeof(*nh));
	if (unlikely(err))
		return err;

	nh = ipv6_hdr(skb);
	nexthdr = nh->nexthdr;
	payload_ofs = (u8 *)(nh + 1) - skb->data;

	key->ip.proto = NEXTHDR_NONE;
	key->ip.tos = ipv6_get_dsfield(nh);
	key->ip.ttl = nh->hop_limit;
	key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
	key->ipv6.addr.src = nh->saddr;
	key->ipv6.addr.dst = nh->daddr;

	payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
	if (unlikely(payload_ofs < 0))
		return -EINVAL;

	if (frag_off) {
		if (frag_off & htons(~0x7))
			key->ip.frag = OVS_FRAG_TYPE_LATER;
		else
			key->ip.frag = OVS_FRAG_TYPE_FIRST;
	}

	nh_len = payload_ofs - nh_ofs;
	skb_set_transport_header(skb, nh_ofs + nh_len);
	key->ip.proto = nexthdr;
	return nh_len;
}

static bool icmp6hdr_ok(struct sk_buff *skb)
{
	return pskb_may_pull(skb, skb_transport_offset(skb) +
				  sizeof(struct icmp6hdr));
}

static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
{
	struct qtag_prefix {
		__be16 eth_type; /* ETH_P_8021Q */
		__be16 tci;
	};
	struct qtag_prefix *qp;

	if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
		return 0;

	if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
					 sizeof(__be16))))
		return -ENOMEM;

	qp = (struct qtag_prefix *) skb->data;
	key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
	__skb_pull(skb, sizeof(struct qtag_prefix));

	return 0;
}

static __be16 parse_ethertype(struct sk_buff *skb)
{
	struct llc_snap_hdr {
		u8  dsap;  /* Always 0xAA */
		u8  ssap;  /* Always 0xAA */
		u8  ctrl;
		u8  oui[3];
		__be16 ethertype;
	};
	struct llc_snap_hdr *llc;
	__be16 proto;

	proto = *(__be16 *) skb->data;
	__skb_pull(skb, sizeof(__be16));

	if (ntohs(proto) >= ETH_P_802_3_MIN)
		return proto;

	if (skb->len < sizeof(struct llc_snap_hdr))
		return htons(ETH_P_802_2);

	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
		return htons(0);

	llc = (struct llc_snap_hdr *) skb->data;
	if (llc->dsap != LLC_SAP_SNAP ||
	    llc->ssap != LLC_SAP_SNAP ||
	    (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
		return htons(ETH_P_802_2);

	__skb_pull(skb, sizeof(struct llc_snap_hdr));

	if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
		return llc->ethertype;

	return htons(ETH_P_802_2);
}

static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
			int nh_len)
{
	struct icmp6hdr *icmp = icmp6_hdr(skb);

	/* The ICMPv6 type and code fields use the 16-bit transport port
	 * fields, so we need to store them in 16-bit network byte order.
	 */
	key->tp.src = htons(icmp->icmp6_type);
	key->tp.dst = htons(icmp->icmp6_code);

	if (icmp->icmp6_code == 0 &&
	    (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
	     icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
		int icmp_len = skb->len - skb_transport_offset(skb);
		struct nd_msg *nd;
		int offset;

		/* In order to process neighbor discovery options, we need the
		 * entire packet.
		 */
		if (unlikely(icmp_len < sizeof(*nd)))
			return 0;

		if (unlikely(skb_linearize(skb)))
			return -ENOMEM;

		nd = (struct nd_msg *)skb_transport_header(skb);
		key->ipv6.nd.target = nd->target;

		icmp_len -= sizeof(*nd);
		offset = 0;
		while (icmp_len >= 8) {
			struct nd_opt_hdr *nd_opt =
				 (struct nd_opt_hdr *)(nd->opt + offset);
			int opt_len = nd_opt->nd_opt_len * 8;

			if (unlikely(!opt_len || opt_len > icmp_len))
				return 0;

			/* Store the link layer address if the appropriate
			 * option is provided.  It is considered an error if
			 * the same link layer option is specified twice.
			 */
			if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
			    && opt_len == 8) {
				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
					goto invalid;
				ether_addr_copy(key->ipv6.nd.sll,
						&nd->opt[offset+sizeof(*nd_opt)]);
			} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
				   && opt_len == 8) {
				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
					goto invalid;
				ether_addr_copy(key->ipv6.nd.tll,
						&nd->opt[offset+sizeof(*nd_opt)]);
			}

			icmp_len -= opt_len;
			offset += opt_len;
		}
	}

	return 0;

invalid:
	memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
	memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
	memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));

	return 0;
}

/**
 * ovs_flow_extract - extracts a flow key from an Ethernet frame.
 * @skb: sk_buff that contains the frame, with skb->data pointing to the
 * Ethernet header
 * @in_port: port number on which @skb was received.
 * @key: output flow key
 *
 * The caller must ensure that skb->len >= ETH_HLEN.
 *
 * Returns 0 if successful, otherwise a negative errno value.
 *
 * Initializes @skb header pointers as follows:
 *
 *    - skb->mac_header: the Ethernet header.
 *
 *    - skb->network_header: just past the Ethernet header, or just past the
 *      VLAN header, to the first byte of the Ethernet payload.
 *
 *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
 *      on output, then just past the IP header, if one is present and
 *      of a correct length, otherwise the same as skb->network_header.
 *      For other key->eth.type values it is left untouched.
 */
int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key)
{
	int error;
	struct ethhdr *eth;

	memset(key, 0, sizeof(*key));

	key->phy.priority = skb->priority;
	if (OVS_CB(skb)->tun_key)
		memcpy(&key->tun_key, OVS_CB(skb)->tun_key, sizeof(key->tun_key));
	key->phy.in_port = in_port;
	key->phy.skb_mark = skb->mark;

	skb_reset_mac_header(skb);

	/* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
	 * header in the linear data area.
	 */
	eth = eth_hdr(skb);
	ether_addr_copy(key->eth.src, eth->h_source);
	ether_addr_copy(key->eth.dst, eth->h_dest);

	__skb_pull(skb, 2 * ETH_ALEN);
	/* We are going to push all headers that we pull, so no need to
	 * update skb->csum here.
	 */

	if (vlan_tx_tag_present(skb))
		key->eth.tci = htons(skb->vlan_tci);
	else if (eth->h_proto == htons(ETH_P_8021Q))
		if (unlikely(parse_vlan(skb, key)))
			return -ENOMEM;

	key->eth.type = parse_ethertype(skb);
	if (unlikely(key->eth.type == htons(0)))
		return -ENOMEM;

	skb_reset_network_header(skb);
	__skb_push(skb, skb->data - skb_mac_header(skb));

	/* Network layer. */
	if (key->eth.type == htons(ETH_P_IP)) {
		struct iphdr *nh;
		__be16 offset;

		error = check_iphdr(skb);
		if (unlikely(error)) {
			if (error == -EINVAL) {
				skb->transport_header = skb->network_header;
				error = 0;
			}
			return error;
		}

		nh = ip_hdr(skb);
		key->ipv4.addr.src = nh->saddr;
		key->ipv4.addr.dst = nh->daddr;

		key->ip.proto = nh->protocol;
		key->ip.tos = nh->tos;
		key->ip.ttl = nh->ttl;

		offset = nh->frag_off & htons(IP_OFFSET);
		if (offset) {
			key->ip.frag = OVS_FRAG_TYPE_LATER;
			return 0;
		}
		if (nh->frag_off & htons(IP_MF) ||
			 skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
			key->ip.frag = OVS_FRAG_TYPE_FIRST;

		/* Transport layer. */
		if (key->ip.proto == IPPROTO_TCP) {
			if (tcphdr_ok(skb)) {
				struct tcphdr *tcp = tcp_hdr(skb);
				key->tp.src = tcp->source;
				key->tp.dst = tcp->dest;
				key->tp.flags = TCP_FLAGS_BE16(tcp);
			}
		} else if (key->ip.proto == IPPROTO_UDP) {
			if (udphdr_ok(skb)) {
				struct udphdr *udp = udp_hdr(skb);
				key->tp.src = udp->source;
				key->tp.dst = udp->dest;
			}
		} else if (key->ip.proto == IPPROTO_SCTP) {
			if (sctphdr_ok(skb)) {
				struct sctphdr *sctp = sctp_hdr(skb);
				key->tp.src = sctp->source;
				key->tp.dst = sctp->dest;
			}
		} else if (key->ip.proto == IPPROTO_ICMP) {
			if (icmphdr_ok(skb)) {
				struct icmphdr *icmp = icmp_hdr(skb);
				/* The ICMP type and code fields use the 16-bit
				 * transport port fields, so we need to store
				 * them in 16-bit network byte order. */
				key->tp.src = htons(icmp->type);
				key->tp.dst = htons(icmp->code);
			}
		}

	} else if ((key->eth.type == htons(ETH_P_ARP) ||
		   key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) {
		struct arp_eth_header *arp;

		arp = (struct arp_eth_header *)skb_network_header(skb);

		if (arp->ar_hrd == htons(ARPHRD_ETHER)
				&& arp->ar_pro == htons(ETH_P_IP)
				&& arp->ar_hln == ETH_ALEN
				&& arp->ar_pln == 4) {

			/* We only match on the lower 8 bits of the opcode. */
			if (ntohs(arp->ar_op) <= 0xff)
				key->ip.proto = ntohs(arp->ar_op);
			memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
			memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
			ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
			ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
		}
	} else if (key->eth.type == htons(ETH_P_IPV6)) {
		int nh_len;             /* IPv6 Header + Extensions */

		nh_len = parse_ipv6hdr(skb, key);
		if (unlikely(nh_len < 0)) {
			if (nh_len == -EINVAL) {
				skb->transport_header = skb->network_header;
				error = 0;
			} else {
				error = nh_len;
			}
			return error;
		}

		if (key->ip.frag == OVS_FRAG_TYPE_LATER)
			return 0;
		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
			key->ip.frag = OVS_FRAG_TYPE_FIRST;

		/* Transport layer. */
		if (key->ip.proto == NEXTHDR_TCP) {
			if (tcphdr_ok(skb)) {
				struct tcphdr *tcp = tcp_hdr(skb);
				key->tp.src = tcp->source;
				key->tp.dst = tcp->dest;
				key->tp.flags = TCP_FLAGS_BE16(tcp);
			}
		} else if (key->ip.proto == NEXTHDR_UDP) {
			if (udphdr_ok(skb)) {
				struct udphdr *udp = udp_hdr(skb);
				key->tp.src = udp->source;
				key->tp.dst = udp->dest;
			}
		} else if (key->ip.proto == NEXTHDR_SCTP) {
			if (sctphdr_ok(skb)) {
				struct sctphdr *sctp = sctp_hdr(skb);
				key->tp.src = sctp->source;
				key->tp.dst = sctp->dest;
			}
		} else if (key->ip.proto == NEXTHDR_ICMP) {
			if (icmp6hdr_ok(skb)) {
				error = parse_icmpv6(skb, key, nh_len);
				if (error)
					return error;
			}
		}
	}

	return 0;
}
Commit	Line	Data
ccb1352e	1	/*
03f0d916	2	* Copyright (c) 2007-2013 Nicira, Inc.
ccb1352e JG	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of version 2 of the GNU General Public
	6	* License as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	11	* General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public License
	14	* along with this program; if not, write to the Free Software
	15	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	16	* 02110-1301, USA
	17	*/
	18
	19	#include "flow.h"
	20	#include "datapath.h"
	21	#include <linux/uaccess.h>
	22	#include <linux/netdevice.h>
	23	#include <linux/etherdevice.h>
	24	#include <linux/if_ether.h>
	25	#include <linux/if_vlan.h>
	26	#include <net/llc_pdu.h>
	27	#include <linux/kernel.h>
	28	#include <linux/jhash.h>
	29	#include <linux/jiffies.h>
	30	#include <linux/llc.h>
	31	#include <linux/module.h>
	32	#include <linux/in.h>
	33	#include <linux/rcupdate.h>
	34	#include <linux/if_arp.h>
ccb1352e JG	35	#include <linux/ip.h>
ccb1352e JG	36	#include <linux/ipv6.h>
a175a723	37	#include <linux/sctp.h>
e298e505	38	#include <linux/smp.h>
ccb1352e JG	39	#include <linux/tcp.h>
	40	#include <linux/udp.h>
	41	#include <linux/icmp.h>
	42	#include <linux/icmpv6.h>
	43	#include <linux/rculist.h>
	44	#include <net/ip.h>
7d5437c7	45	#include <net/ip_tunnels.h>
ccb1352e JG	46	#include <net/ipv6.h>
	47	#include <net/ndisc.h>
	48
e6445719	49	u64 ovs_flow_used_time(unsigned long flow_jiffies)
03f0d916	50	{
e6445719 PS	51	struct timespec cur_ts;
e6445719 PS	52	u64 cur_ms, idle_ms;
03f0d916	53
e6445719 PS	54	ktime_get_ts(&cur_ts);
	55	idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
	56	cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
	57	cur_ts.tv_nsec / NSEC_PER_MSEC;
03f0d916	58
e6445719	59	return cur_ms - idle_ms;
5828cd9a AZ	60	}
5828cd9a AZ	61
df23e9f6	62	#define TCP_FLAGS_BE16(tp) ((__be16 )&tcp_flag_word(tp) & htons(0x0FFF))
03f0d916	63
e298e505	64	void ovs_flow_stats_update(struct sw_flow flow, struct sk_buff skb)
03f0d916	65	{
e298e505	66	struct flow_stats *stats;
1139e241	67	__be16 tcp_flags = flow->key.tp.flags;
63e7959c	68	int node = numa_node_id();
03f0d916	69
63e7959c	70	stats = rcu_dereference(flow->stats[node]);
e298e505	71
63e7959c JR	72	/* Check if already have node-specific stats. */
	73	if (likely(stats)) {
	74	spin_lock(&stats->lock);
	75	/* Mark if we write on the pre-allocated stats. */
	76	if (node == 0 && unlikely(flow->stats_last_writer != node))
	77	flow->stats_last_writer = node;
	78	} else {
	79	stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
	80	spin_lock(&stats->lock);
	81
	82	/* If the current NUMA-node is the only writer on the
	83	* pre-allocated stats keep using them.
	84	*/
	85	if (unlikely(flow->stats_last_writer != node)) {
	86	/* A previous locker may have already allocated the
	87	* stats, so we need to check again. If node-specific
	88	* stats were already allocated, we update the pre-
	89	* allocated stats as we have already locked them.
	90	*/
	91	if (likely(flow->stats_last_writer != NUMA_NO_NODE)
	92	&& likely(!rcu_dereference(flow->stats[node]))) {
	93	/* Try to allocate node-specific stats. */
	94	struct flow_stats *new_stats;
	95
	96	new_stats =
	97	kmem_cache_alloc_node(flow_stats_cache,
	98	GFP_THISNODE \|
	99	__GFP_NOMEMALLOC,
	100	node);
	101	if (likely(new_stats)) {
	102	new_stats->used = jiffies;
	103	new_stats->packet_count = 1;
	104	new_stats->byte_count = skb->len;
	105	new_stats->tcp_flags = tcp_flags;
	106	spin_lock_init(&new_stats->lock);
	107
	108	rcu_assign_pointer(flow->stats[node],
	109	new_stats);
	110	goto unlock;
	111	}
	112	}
	113	flow->stats_last_writer = node;
	114	}
	115	}
	116
e298e505 PS	117	stats->used = jiffies;
	118	stats->packet_count++;
	119	stats->byte_count += skb->len;
	120	stats->tcp_flags \|= tcp_flags;
63e7959c	121	unlock:
e298e505 PS	122	spin_unlock(&stats->lock);
	123	}
	124
bb6f9a70	125	/* Called with ovs_mutex. */
e298e505 PS	126	void ovs_flow_stats_get(struct sw_flow flow, struct ovs_flow_stats ovs_stats,
	127	unsigned long used, __be16 tcp_flags)
	128	{
63e7959c	129	int node;
e298e505 PS	130
	131	*used = 0;
	132	*tcp_flags = 0;
	133	memset(ovs_stats, 0, sizeof(*ovs_stats));
	134
63e7959c	135	for_each_node(node) {
bb6f9a70	136	struct flow_stats *stats = ovsl_dereference(flow->stats[node]);
63e7959c JR	137
	138	if (stats) {
	139	/* Local CPU may write on non-local stats, so we must
	140	* block bottom-halves here.
	141	*/
	142	spin_lock_bh(&stats->lock);
	143	if (!used \|\| time_after(stats->used, used))
	144	*used = stats->used;
	145	*tcp_flags \|= stats->tcp_flags;
	146	ovs_stats->n_packets += stats->packet_count;
	147	ovs_stats->n_bytes += stats->byte_count;
	148	spin_unlock_bh(&stats->lock);
	149	}
e298e505	150	}
e298e505 PS	151	}
	152
	153	void ovs_flow_stats_clear(struct sw_flow *flow)
	154	{
63e7959c JR	155	int node;
	156
	157	for_each_node(node) {
	158	struct flow_stats *stats = rcu_dereference(flow->stats[node]);
	159
	160	if (stats) {
	161	spin_lock_bh(&stats->lock);
	162	stats->used = 0;
	163	stats->packet_count = 0;
	164	stats->byte_count = 0;
	165	stats->tcp_flags = 0;
	166	spin_unlock_bh(&stats->lock);
	167	}
	168	}
03f0d916 AZ	169	}
03f0d916 AZ	170
ccb1352e JG	171	static int check_header(struct sk_buff *skb, int len)
	172	{
	173	if (unlikely(skb->len < len))
	174	return -EINVAL;
	175	if (unlikely(!pskb_may_pull(skb, len)))
	176	return -ENOMEM;
	177	return 0;
	178	}
	179
	180	static bool arphdr_ok(struct sk_buff *skb)
	181	{
	182	return pskb_may_pull(skb, skb_network_offset(skb) +
	183	sizeof(struct arp_eth_header));
	184	}
	185
	186	static int check_iphdr(struct sk_buff *skb)
	187	{
	188	unsigned int nh_ofs = skb_network_offset(skb);
	189	unsigned int ip_len;
	190	int err;
	191
	192	err = check_header(skb, nh_ofs + sizeof(struct iphdr));
	193	if (unlikely(err))
	194	return err;
	195
	196	ip_len = ip_hdrlen(skb);
	197	if (unlikely(ip_len < sizeof(struct iphdr) \|\|
	198	skb->len < nh_ofs + ip_len))
	199	return -EINVAL;
	200
	201	skb_set_transport_header(skb, nh_ofs + ip_len);
	202	return 0;
	203	}
	204
	205	static bool tcphdr_ok(struct sk_buff *skb)
	206	{
	207	int th_ofs = skb_transport_offset(skb);
	208	int tcp_len;
	209
	210	if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
	211	return false;
	212
	213	tcp_len = tcp_hdrlen(skb);
	214	if (unlikely(tcp_len < sizeof(struct tcphdr) \|\|
	215	skb->len < th_ofs + tcp_len))
	216	return false;
	217
	218	return true;
	219	}
	220
	221	static bool udphdr_ok(struct sk_buff *skb)
	222	{
	223	return pskb_may_pull(skb, skb_transport_offset(skb) +
	224	sizeof(struct udphdr));
	225	}
	226
a175a723 JS	227	static bool sctphdr_ok(struct sk_buff *skb)
	228	{
	229	return pskb_may_pull(skb, skb_transport_offset(skb) +
	230	sizeof(struct sctphdr));
	231	}
	232
ccb1352e JG	233	static bool icmphdr_ok(struct sk_buff *skb)
	234	{
	235	return pskb_may_pull(skb, skb_transport_offset(skb) +
	236	sizeof(struct icmphdr));
	237	}
	238
03f0d916	239	static int parse_ipv6hdr(struct sk_buff skb, struct sw_flow_key key)
ccb1352e JG	240	{
	241	unsigned int nh_ofs = skb_network_offset(skb);
	242	unsigned int nh_len;
	243	int payload_ofs;
	244	struct ipv6hdr *nh;
	245	uint8_t nexthdr;
	246	__be16 frag_off;
	247	int err;
	248
ccb1352e JG	249	err = check_header(skb, nh_ofs + sizeof(*nh));
	250	if (unlikely(err))
	251	return err;
	252
	253	nh = ipv6_hdr(skb);
	254	nexthdr = nh->nexthdr;
	255	payload_ofs = (u8 *)(nh + 1) - skb->data;
	256
	257	key->ip.proto = NEXTHDR_NONE;
	258	key->ip.tos = ipv6_get_dsfield(nh);
	259	key->ip.ttl = nh->hop_limit;
	260	key->ipv6.label = (__be32 )nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
	261	key->ipv6.addr.src = nh->saddr;
	262	key->ipv6.addr.dst = nh->daddr;
	263
	264	payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
	265	if (unlikely(payload_ofs < 0))
	266	return -EINVAL;
	267
	268	if (frag_off) {
	269	if (frag_off & htons(~0x7))
	270	key->ip.frag = OVS_FRAG_TYPE_LATER;
	271	else
	272	key->ip.frag = OVS_FRAG_TYPE_FIRST;
	273	}
	274
	275	nh_len = payload_ofs - nh_ofs;
	276	skb_set_transport_header(skb, nh_ofs + nh_len);
	277	key->ip.proto = nexthdr;
	278	return nh_len;
	279	}
	280
	281	static bool icmp6hdr_ok(struct sk_buff *skb)
	282	{
	283	return pskb_may_pull(skb, skb_transport_offset(skb) +
	284	sizeof(struct icmp6hdr));
	285	}
	286
ccb1352e JG	287	static int parse_vlan(struct sk_buff skb, struct sw_flow_key key)
	288	{
	289	struct qtag_prefix {
	290	__be16 eth_type; /* ETH_P_8021Q */
	291	__be16 tci;
	292	};
	293	struct qtag_prefix *qp;
	294
	295	if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
	296	return 0;
	297
	298	if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
	299	sizeof(__be16))))
	300	return -ENOMEM;
	301
	302	qp = (struct qtag_prefix *) skb->data;
	303	key->eth.tci = qp->tci \| htons(VLAN_TAG_PRESENT);
	304	__skb_pull(skb, sizeof(struct qtag_prefix));
	305
	306	return 0;
	307	}
	308
	309	static __be16 parse_ethertype(struct sk_buff *skb)
	310	{
	311	struct llc_snap_hdr {
	312	u8 dsap; /* Always 0xAA */
	313	u8 ssap; /* Always 0xAA */
	314	u8 ctrl;
	315	u8 oui[3];
	316	__be16 ethertype;
	317	};
	318	struct llc_snap_hdr *llc;
	319	__be16 proto;
	320
	321	proto = (__be16 ) skb->data;
	322	__skb_pull(skb, sizeof(__be16));
	323
e5c5d22e	324	if (ntohs(proto) >= ETH_P_802_3_MIN)
ccb1352e JG	325	return proto;
	326
	327	if (skb->len < sizeof(struct llc_snap_hdr))
	328	return htons(ETH_P_802_2);
	329
	330	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
	331	return htons(0);
	332
	333	llc = (struct llc_snap_hdr *) skb->data;
	334	if (llc->dsap != LLC_SAP_SNAP \|\|
	335	llc->ssap != LLC_SAP_SNAP \|\|
	336	(llc->oui[0] \| llc->oui[1] \| llc->oui[2]) != 0)
	337	return htons(ETH_P_802_2);
	338
	339	__skb_pull(skb, sizeof(struct llc_snap_hdr));
17b682a0	340
e5c5d22e	341	if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
17b682a0 RL	342	return llc->ethertype;
	343
	344	return htons(ETH_P_802_2);
ccb1352e JG	345	}
	346
	347	static int parse_icmpv6(struct sk_buff skb, struct sw_flow_key key,
03f0d916	348	int nh_len)
ccb1352e JG	349	{
ccb1352e JG	350	struct icmp6hdr *icmp = icmp6_hdr(skb);
ccb1352e JG	351
	352	/* The ICMPv6 type and code fields use the 16-bit transport port
	353	* fields, so we need to store them in 16-bit network byte order.
	354	*/
1139e241 JR	355	key->tp.src = htons(icmp->icmp6_type);
1139e241 JR	356	key->tp.dst = htons(icmp->icmp6_code);
ccb1352e JG	357
	358	if (icmp->icmp6_code == 0 &&
	359	(icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION \|\|
	360	icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
	361	int icmp_len = skb->len - skb_transport_offset(skb);
	362	struct nd_msg *nd;
	363	int offset;
	364
ccb1352e JG	365	/* In order to process neighbor discovery options, we need the
	366	* entire packet.
	367	*/
	368	if (unlikely(icmp_len < sizeof(*nd)))
03f0d916 AZ	369	return 0;
	370
	371	if (unlikely(skb_linearize(skb)))
	372	return -ENOMEM;
ccb1352e JG	373
	374	nd = (struct nd_msg *)skb_transport_header(skb);
	375	key->ipv6.nd.target = nd->target;
ccb1352e JG	376
	377	icmp_len -= sizeof(*nd);
	378	offset = 0;
	379	while (icmp_len >= 8) {
	380	struct nd_opt_hdr *nd_opt =
	381	(struct nd_opt_hdr *)(nd->opt + offset);
	382	int opt_len = nd_opt->nd_opt_len * 8;
	383
	384	if (unlikely(!opt_len \|\| opt_len > icmp_len))
03f0d916	385	return 0;
ccb1352e JG	386
	387	/* Store the link layer address if the appropriate
	388	* option is provided. It is considered an error if
	389	* the same link layer option is specified twice.
	390	*/
	391	if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
	392	&& opt_len == 8) {
	393	if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
	394	goto invalid;
8c63ff09 JP	395	ether_addr_copy(key->ipv6.nd.sll,
8c63ff09 JP	396	&nd->opt[offset+sizeof(*nd_opt)]);
ccb1352e JG	397	} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
	398	&& opt_len == 8) {
	399	if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
	400	goto invalid;
8c63ff09 JP	401	ether_addr_copy(key->ipv6.nd.tll,
8c63ff09 JP	402	&nd->opt[offset+sizeof(*nd_opt)]);
ccb1352e JG	403	}
	404
	405	icmp_len -= opt_len;
	406	offset += opt_len;
	407	}
	408	}
	409
03f0d916	410	return 0;
ccb1352e JG	411
	412	invalid:
	413	memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
	414	memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
	415	memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
	416
03f0d916	417	return 0;
ccb1352e JG	418	}
	419
	420	/**
	421	* ovs_flow_extract - extracts a flow key from an Ethernet frame.
	422	* @skb: sk_buff that contains the frame, with skb->data pointing to the
	423	* Ethernet header
	424	* @in_port: port number on which @skb was received.
	425	* @key: output flow key
ccb1352e JG	426	*
	427	* The caller must ensure that skb->len >= ETH_HLEN.
	428	*
	429	* Returns 0 if successful, otherwise a negative errno value.
	430	*
	431	* Initializes @skb header pointers as follows:
	432	*
	433	* - skb->mac_header: the Ethernet header.
	434	*
	435	* - skb->network_header: just past the Ethernet header, or just past the
	436	* VLAN header, to the first byte of the Ethernet payload.
	437	*
34d94f21	438	* - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
ccb1352e JG	439	* on output, then just past the IP header, if one is present and
ccb1352e JG	440	* of a correct length, otherwise the same as skb->network_header.
34d94f21	441	* For other key->eth.type values it is left untouched.
ccb1352e	442	*/
03f0d916	443	int ovs_flow_extract(struct sk_buff skb, u16 in_port, struct sw_flow_key key)
ccb1352e	444	{
03f0d916	445	int error;
ccb1352e JG	446	struct ethhdr *eth;
	447
	448	memset(key, 0, sizeof(*key));
	449
	450	key->phy.priority = skb->priority;
7d5437c7 PS	451	if (OVS_CB(skb)->tun_key)
7d5437c7 PS	452	memcpy(&key->tun_key, OVS_CB(skb)->tun_key, sizeof(key->tun_key));
ccb1352e	453	key->phy.in_port = in_port;
39c7caeb	454	key->phy.skb_mark = skb->mark;
ccb1352e JG	455
	456	skb_reset_mac_header(skb);
	457
	458	/* Link layer. We are guaranteed to have at least the 14 byte Ethernet
	459	* header in the linear data area.
	460	*/
	461	eth = eth_hdr(skb);
8c63ff09 JP	462	ether_addr_copy(key->eth.src, eth->h_source);
8c63ff09 JP	463	ether_addr_copy(key->eth.dst, eth->h_dest);
ccb1352e JG	464
ccb1352e JG	465	__skb_pull(skb, 2 * ETH_ALEN);
b34df5e8 PS	466	/* We are going to push all headers that we pull, so no need to
	467	* update skb->csum here.
	468	*/
ccb1352e JG	469
	470	if (vlan_tx_tag_present(skb))
	471	key->eth.tci = htons(skb->vlan_tci);
	472	else if (eth->h_proto == htons(ETH_P_8021Q))
	473	if (unlikely(parse_vlan(skb, key)))
	474	return -ENOMEM;
	475
	476	key->eth.type = parse_ethertype(skb);
	477	if (unlikely(key->eth.type == htons(0)))
	478	return -ENOMEM;
	479
	480	skb_reset_network_header(skb);
	481	__skb_push(skb, skb->data - skb_mac_header(skb));
	482
	483	/* Network layer. */
	484	if (key->eth.type == htons(ETH_P_IP)) {
	485	struct iphdr *nh;
	486	__be16 offset;
	487
ccb1352e JG	488	error = check_iphdr(skb);
	489	if (unlikely(error)) {
	490	if (error == -EINVAL) {
	491	skb->transport_header = skb->network_header;
	492	error = 0;
	493	}
03f0d916	494	return error;
ccb1352e JG	495	}
	496
	497	nh = ip_hdr(skb);
	498	key->ipv4.addr.src = nh->saddr;
	499	key->ipv4.addr.dst = nh->daddr;
	500
	501	key->ip.proto = nh->protocol;
	502	key->ip.tos = nh->tos;
	503	key->ip.ttl = nh->ttl;
	504
	505	offset = nh->frag_off & htons(IP_OFFSET);
	506	if (offset) {
	507	key->ip.frag = OVS_FRAG_TYPE_LATER;
03f0d916	508	return 0;
ccb1352e JG	509	}
	510	if (nh->frag_off & htons(IP_MF) \|\|
	511	skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
	512	key->ip.frag = OVS_FRAG_TYPE_FIRST;
	513
	514	/* Transport layer. */
	515	if (key->ip.proto == IPPROTO_TCP) {
ccb1352e JG	516	if (tcphdr_ok(skb)) {
ccb1352e JG	517	struct tcphdr *tcp = tcp_hdr(skb);
1139e241 JR	518	key->tp.src = tcp->source;
	519	key->tp.dst = tcp->dest;
	520	key->tp.flags = TCP_FLAGS_BE16(tcp);
ccb1352e JG	521	}
ccb1352e JG	522	} else if (key->ip.proto == IPPROTO_UDP) {
ccb1352e JG	523	if (udphdr_ok(skb)) {
ccb1352e JG	524	struct udphdr *udp = udp_hdr(skb);
1139e241 JR	525	key->tp.src = udp->source;
1139e241 JR	526	key->tp.dst = udp->dest;
ccb1352e	527	}
a175a723 JS	528	} else if (key->ip.proto == IPPROTO_SCTP) {
	529	if (sctphdr_ok(skb)) {
	530	struct sctphdr *sctp = sctp_hdr(skb);
1139e241 JR	531	key->tp.src = sctp->source;
1139e241 JR	532	key->tp.dst = sctp->dest;
a175a723	533	}
ccb1352e	534	} else if (key->ip.proto == IPPROTO_ICMP) {
ccb1352e JG	535	if (icmphdr_ok(skb)) {
	536	struct icmphdr *icmp = icmp_hdr(skb);
	537	/* The ICMP type and code fields use the 16-bit
	538	* transport port fields, so we need to store
	539	* them in 16-bit network byte order. */
1139e241 JR	540	key->tp.src = htons(icmp->type);
1139e241 JR	541	key->tp.dst = htons(icmp->code);
ccb1352e JG	542	}
	543	}
	544
c0618533 MM	545	} else if ((key->eth.type == htons(ETH_P_ARP) \|\|
c0618533 MM	546	key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) {
ccb1352e JG	547	struct arp_eth_header *arp;
	548
	549	arp = (struct arp_eth_header *)skb_network_header(skb);
	550
	551	if (arp->ar_hrd == htons(ARPHRD_ETHER)
	552	&& arp->ar_pro == htons(ETH_P_IP)
	553	&& arp->ar_hln == ETH_ALEN
	554	&& arp->ar_pln == 4) {
	555
	556	/* We only match on the lower 8 bits of the opcode. */
	557	if (ntohs(arp->ar_op) <= 0xff)
	558	key->ip.proto = ntohs(arp->ar_op);
d04d3829 MM	559	memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
d04d3829 MM	560	memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
8c63ff09 JP	561	ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
8c63ff09 JP	562	ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
ccb1352e JG	563	}
	564	} else if (key->eth.type == htons(ETH_P_IPV6)) {
	565	int nh_len; /* IPv6 Header + Extensions */
	566
03f0d916	567	nh_len = parse_ipv6hdr(skb, key);
ccb1352e	568	if (unlikely(nh_len < 0)) {
03f0d916	569	if (nh_len == -EINVAL) {
ccb1352e	570	skb->transport_header = skb->network_header;
03f0d916 AZ	571	error = 0;
03f0d916 AZ	572	} else {
ccb1352e	573	error = nh_len;
03f0d916 AZ	574	}
03f0d916 AZ	575	return error;
ccb1352e JG	576	}
	577
	578	if (key->ip.frag == OVS_FRAG_TYPE_LATER)
03f0d916	579	return 0;
ccb1352e JG	580	if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
	581	key->ip.frag = OVS_FRAG_TYPE_FIRST;
	582
	583	/* Transport layer. */
	584	if (key->ip.proto == NEXTHDR_TCP) {
ccb1352e JG	585	if (tcphdr_ok(skb)) {
ccb1352e JG	586	struct tcphdr *tcp = tcp_hdr(skb);
1139e241 JR	587	key->tp.src = tcp->source;
	588	key->tp.dst = tcp->dest;
	589	key->tp.flags = TCP_FLAGS_BE16(tcp);
ccb1352e JG	590	}
ccb1352e JG	591	} else if (key->ip.proto == NEXTHDR_UDP) {
ccb1352e JG	592	if (udphdr_ok(skb)) {
ccb1352e JG	593	struct udphdr *udp = udp_hdr(skb);
1139e241 JR	594	key->tp.src = udp->source;
1139e241 JR	595	key->tp.dst = udp->dest;
ccb1352e	596	}
a175a723 JS	597	} else if (key->ip.proto == NEXTHDR_SCTP) {
	598	if (sctphdr_ok(skb)) {
	599	struct sctphdr *sctp = sctp_hdr(skb);
1139e241 JR	600	key->tp.src = sctp->source;
1139e241 JR	601	key->tp.dst = sctp->dest;
a175a723	602	}
ccb1352e	603	} else if (key->ip.proto == NEXTHDR_ICMP) {
ccb1352e	604	if (icmp6hdr_ok(skb)) {
03f0d916 AZ	605	error = parse_icmpv6(skb, key, nh_len);
	606	if (error)
	607	return error;
ccb1352e JG	608	}
	609	}
	610	}
	611
03f0d916	612	return 0;
ccb1352e	613	}